Creation of mortality risk charts using 123I meta-iodobenzylguanidine heart-To-mediastinum ratio in patients with heart failure: 2-And 5-year risk models

Abstract

Aims 123I meta-iodobenzylguanidine (MIBG) imaging has been extensively used for prognostication in patients with chronic heart failure (CHF). The purpose of this study was to create mortality risk charts for short-Term (2 years) and long-Term (5 years) prediction of cardiac mortality. Methods and results Using a pooled database of 1322 CHF patients, multivariate analysis, including 123I-MIBG late heart-To-mediastinum ratio (HMR), left ventricular ejection fraction (LVEF), and clinical factors, was performed to determine optimal variables for the prediction of 2-And 5-year mortality risk using subsets of the patients (n= 1280 and 933, respectively). Multivariate logistic regression analysis was performed to create risk charts. Cardiac mortality was 10 and 22% for the subpopulation of 2-And 5-year analyses. A four-parameter multivariate logistic regression model including age, New York Heart Association (NYHA) functional class, LVEF, and HMR was used. Annualized mortality rate was ,1% in patients with NYHA Class I-II and HMR ≥ 2.0, irrespective of age and LVEF. In patients with NYHA Class III-IV, mortality rate was 4-6 times higher for HMR , 1.40 compared with HMR ≥ 2.0 in all LVEF classes. Among the subset of patients with b-Type natriuretic peptide (BNP) results (n= 491 and 359 for 2-And 5-year models, respectively), the 5-year model showed incremental value of HMR in addition to BNP. Conclusion Both 2-And 5-year risk prediction models with 123I-MIBG HMR can be used to identify low-risk as well as high-risk patients, which can be effective for further risk stratification of CHF patients even when BNP is available.